U.S. patent application number 17/126920 was filed with the patent office on 2021-06-24 for systems and methods for extended proximate sensing in a vehicle.
The applicant listed for this patent is Joyson Safety Systems Acquisition LLC. Invention is credited to Dwayne Van'tZelfde.
Application Number | 20210191540 17/126920 |
Document ID | / |
Family ID | 1000005327967 |
Filed Date | 2021-06-24 |
United States Patent
Application |
20210191540 |
Kind Code |
A1 |
Van'tZelfde; Dwayne |
June 24, 2021 |
SYSTEMS AND METHODS FOR EXTENDED PROXIMATE SENSING IN A VEHICLE
Abstract
A sensor system includes a first electrode serving as a primary
electrode with a controller electrically and physically coupled to
the first electrode. Computer executable instructions execute
software commands on the controller causing the controller to apply
a voltage to the first electrode to generate an electric field
around the first electrode. A second electrode has at least a
portion of the second electrode being disposed within the
electrical field generated by the first electrode, and the second
electrode operates while being physically decoupled from the
controller. The electrical field generated by the first electrode
induces a corresponding charge on the second electrode, and
proximity of a conductive material on or near the first or second
electrode alters the electrical signal received back by the
controller from the first electrode to allow for sensing the
conductive material.
Inventors: |
Van'tZelfde; Dwayne; (Holly,
MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Joyson Safety Systems Acquisition LLC |
Auburn Hills |
MI |
US |
|
|
Family ID: |
1000005327967 |
Appl. No.: |
17/126920 |
Filed: |
December 18, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62951296 |
Dec 20, 2019 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B62D 1/046 20130101;
G06F 3/0383 20130101; G06F 3/044 20130101; H03K 17/955
20130101 |
International
Class: |
G06F 3/044 20060101
G06F003/044; B62D 1/04 20060101 B62D001/04; H03K 17/955 20060101
H03K017/955; G06F 3/038 20060101 G06F003/038 |
Claims
1. A sensor system comprising: a first electrode; a controller
electrically and physically coupled to the first electrode, the
controller having a processor and a memory, the memory storing
computer executable instructions for execution by the processor,
the computer executable instructions causing the processor to
receive an electrical signal from the first electrode; a second
electrode, at least a portion of the second electrode being
disposed within an electrical field generated by the first
electrode, the second electrode being physically decoupled from the
controller, wherein the electrical field generated by the first
electrode induces a corresponding charge on the second electrode,
and proximity of a conductive material to the first or second
electrode alters the electrical signal received by the controller
from the first electrode.
2. The sensor system of claim 1, wherein a controller output
transmitted to the first electrode induces the electric field and
sets a baseline signal for comparing to the electrical signal
received by the processor.
3. The sensor system of claim 1, wherein at least a portion of the
second electrode is in a position that is spaced apart from and
extends alongside at least a corresponding portion of the first
electrode.
4. The sensor system of claim 3, wherein entireties of both the
second electrode and the first electrode are spaced apart from each
other.
5. The sensor system of claim 1, wherein the first electrode is
disposed on a first substrate, and the second electrode is disposed
on a second substrate, the first substrate being spaced apart from
the second substrate.
6. The sensor system of claim 5, wherein in an x-y-z coordinate
system, the first substrate and the second substrate overlap at a
plurality of x-axis and y-axis coordinates and are spaced apart
along a z-axis, the system further comprising an adhesive extending
between overlapping regions of the first substrate and the second
substrate.
7. The sensor system of claim 1, wherein the first electrode is
disposed on a first side of a substrate and the second electrode is
disposed on a second side of the substrate, wherein the first and
second sides are opposite and spaced apart from each other.
8. The sensor system of claim 1, wherein a perimeter of the second
electrode is within and spaced apart from a respective perimeter of
the first electrode.
9. The sensor system of claim 1, wherein the controller transmits a
first electrical input to the first electrode that generates heat
directed to a steering wheel of a vehicle and the controller
transmits a second electrical input to the first electrode that
induces the corresponding charge on the second electrode, wherein
the first and second electrical inputs are time multiplexed.
10. The sensor system of claim 1, further comprising a third
electrode disposed between a steering wheel frame and the first and
second electrodes as a pair, the third electrode being physically
and electrically coupled to the controller, and the computer
executable instructions further cause the processor to transmit a
third electrical output to the third electrode that shields the
first electrical input and the second electrical input on the first
electrode from the frame of the steering wheel.
11. The sensor system of claim 1, wherein the first electrode has a
first end portion and a second end portion, the first end portion
being physically coupled to the controller and the second end
portion being spaced apart from the first end portion, and a
respective end portion of the second electrode is disposed adjacent
the second end portion of the first electrode within the electric
field of the second end portion of the first electrode.
12. The sensor system of claim 1, wherein an adhesive layer is
disposed between at least a portion of the first electrode and the
second electrode.
13. The sensor system of claim 12, wherein the adhesive layer is
non-conductive.
14. The sensor system of claim 1, wherein at least a portion of the
first and/or second electrode is disposed adjacent a rim portion of
a steering wheel frame.
15. The sensor system of claim 1, wherein the first and second
electrodes are disposed adjacent a seat frame in a vehicle.
16. A sensor system, comprising: a primary electrode positioned
within an accessible object; a controller comprising a charging
source that charges the primary electrode, wherein, upon the
charging, the controller is configured to receive an electrical
signal back from the primary electrode; a floating electrode that
is mechanically disconnected from outside charging sources, wherein
at least a portion of the floating electrode is aligned with the
primary electrode within the accessible object such that upon the
charging of the first electrode, the second electrode exhibits an
induced current thereon; wherein, proximity of a conductive
material to either the primary electrode or the floating electrode
induces capacitive coupling between the conductive material and the
respective primary or floating electrode that alters the electrical
signal received by the controller from the first electrode; and
wherein the controller is configured to track a response of the
electrical signal to the capacitive coupling.
17. A sensor system according to claim 16, wherein the portion of
the floating electrode aligned with the primary electrode is also
spaced apart from the primary electrode, such that when the
conductive material is proximate the aligned portion of the
floating electrode, the capacitive coupling changes a baseline
capacitance at the aligned portion present upon charging the
primary electrode.
18. A sensor system according to claim 17, wherein the primary
electrode is a heating element and the floating electrode is a
capacitive sensing element.
19. A sensor system according to claim 16, wherein the controller
uses the electrical signal to identify changes in an electrical
field strength about the primary electrode due to the proximity of
the conductive material.
20. A sensor system according to claim 19, wherein changes in the
corresponding electrical field strength about the secondary
electrode cause a detectable change in the electrical field
strength about the primary electrode.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and incorporates by
reference U.S. Provisional Patent Application Ser. No. 62/951,296
filed on Dec. 20, 2019, and entitled "Systems and Methods for
Extended Proximate Sensing in a Vehicle.
BACKGROUND
[0002] Current vehicle components, including but not limited to
steering wheel designs, may include a sensor mat disposed thereon
for occupancy detection, occupancy classification, and vehicle
control system programming. Prior embodiments of this technology,
for example, are used to wrap around a rim of a steering wheel or
placed in a seat cushion such that associated electronics detect
presence and position of one or more occupants. In one prior art
embodiment, the sensors utilize capacitive sensing technology to
identify hands on the steering wheel rim. The sensor mat is
disposed between an outer skin of the steering wheel and a rim of a
steering wheel frame. The steering wheel frame is typically made of
metal, such as a magnesium alloy or steel, and can be a source of
interference for the electrical signal(s) in the sensor mat. Other
embodiments of capacitive sensing technology utilize similar
sensors on substrates for installations in seats, armrests, or any
occupant accessible vehicle component that can provide useful data
to a vehicle computer. Most of these sensors include data
transmission media for sending and receiving appropriate signals to
and from the sensor.
[0003] According to various prior implementations, such as the
prior art embodiments of FIGS. 1A-1E, vehicle sensor systems often
utilize a sensor mat 8, a shield mat 7, and an electronic control
unit (ECU) 200 illustrated as incorporating numerous computerized
components in FIG. 1E. The sensor mat includes one or more sensing
loop circuits 22a, 22b, 22c positioned on a sensor mat substrate 16
and in communication with the ECU via communications connections
36a, 36b, 36c. Each of the sensing loops defines a sensing zone
24a, 24b, 24c as illustrated in FIG. 1B.
[0004] In some earlier embodiments, the shield mat 7 may be
disposed between the sensor mat 8 and an interfering object, such
as a metal steering wheel frame 12 of FIG. 1A or a metal seat frame
or a separate heater installation. The shield mat 7 is shown by
illustration in FIG. 1D and typically includes one or more
conductive loops 24a, 24b, 24c positioned on a shield mat substrate
18 and in communication with the ECU via corresponding
communication circuits 34A, 34b, 34c. The sensing loops and the
shielding conductive loops are configured for operation with an
electronic control unit (ECU) 200 that is in communication with the
sensor mat and the shield mat and includes a power source
configured for generating respective voltage that allow for
operating one or more sensing zones of the sensor mat and shielding
the sensor mat from interference.
[0005] Prior art systems may also use the sensor mats and shielding
mats in the presence of an existing heater installation such as
heater mat 6 of FIG. 1 similarly set up in heating zones 52a, 52b,
52c, from which the sensor mat 8 also requires shielding, or in at
least one implementation, either the sensor mat or the shielding
mat may be configured to operate as a heater during a portion of
the ECU power management duty cycle.
[0006] With the continued growth of automation in vehicle
operation, and with smart control systems managed by a vehicle CPU
in modern transportation systems, manufacturers have been searching
for ways to install the above noted sensor technology in more
obscure areas all over the vehicle. Some of these installations
require close fitting construction in hard to reach areas of the
vehicle where return wiring or other transmission media are hard to
locate but are necessary for communication with vehicle computers,
including ECU 200 of FIG. 1E.
[0007] Accordingly, there is a need in the art for improved sensing
apparatuses and systems that take into account sensor placement in
tight fitting vehicle components. Also, as described above, current
hand and occupant detection sensors, for implementations including
but not limited to hands on wheel steering wheel controls, rely on
making a physical connection to the sensing circuit (i.e., the
sensor zone). The circuit itself may be positioned, for example,
around a steering wheel rim. Once positioned on the wheel, the
sensor zone is connected to a capacitive sensing controller via the
electronic control unit (ECU). Without the physical electrical
connection from the ECU to the sensor zone(s), the sensing area
will not be functional. The sensing area and density of the sensor
may be limited by the material technology, for example
multi-stranded copper wire is stitched with a spacing of -2 mm to
increase the effective surface density. Limitations exist with the
wire stitching technology such that a higher density increases risk
of damaging the neighboring wires. These issues present another
opportunity to advance sensing technology with at least one goal of
increasing the effective sensor surface area while retaining the
benefits of current manufacturing systems, such as stitched wire
sensors.
BRIEF SUMMARY
[0008] A sensor system includes a first electrode 216 serving as a
primary electrode with a controller 200 electrically and physically
coupled to the first electrode 216. The controller has computerized
hardware such as a processor and a memory, the memory storing
computer executable instructions for execution by the processor.
The computer executable instructions execute software commands that
apply a voltage to the first electrode 216 to generate an electric
field around the first electrode, which in turn causes the
processor to receive an electrical signal back from the first
electrode via a connected circuit 236. The system further includes
a second electrode 266, at least a portion of the second electrode
being disposed within the electrical field generated by the first
electrode, and the second electrode 266 operates while being
physically decoupled from the controller 200. The electrical field
generated by the first electrode 216 induces a corresponding charge
on the second electrode 266, and proximity of a conductive material
on or near the first or second electrode alters the electrical
signal received back by the controller 200 from the first electrode
216. The conductive material may be a vehicle occupant's hand,
another body part, or any object that alters the electric field
exhibited by the first electrode 216. The sensor system of FIG. 2A
illustrates that a controller output transmitted to the first
electrode via connected circuit 236 induces the electric field and
sets a baseline signal for comparing to the electrical signal
received back from the first electrode 216 by the controller
processor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The components in the drawings are not necessarily to scale
relative to each other. Like reference numerals designate
corresponding parts throughout the several views.
[0010] FIG. 1A illustrates a PRIOR ART cross sectional view of
layers in a steering wheel according to one implementation of this
disclosure.
[0011] FIG. 1B illustrates a PRIOR ART perspective view of a sensor
mat layer, a shield mat layer, and heater mat layer according to
the implementation in FIG. 1A.
[0012] FIG. 1C illustrates a PRIOR ART schematic diagram of the
sensor mat circuits implemented in the example of FIGS. 1A and
1B.
[0013] FIG. 1D illustrates a PRIOR ART schematic diagram of the
shielding mat circuits of FIGS. 1A and 1B.
[0014] FIG. 1E is a PRIOR ART schematic of an example ECU with
computerized hardware that may be used in conjunction with the
embodiments of this disclosure.
[0015] FIG. 2A illustrates a top view of proximate sensing
substrate positions according to one implementation of this
disclosure.
[0016] FIG. 2B illustrates a cross section view of the proximate
sensing substrate positions according to the embodiment of FIG.
2A.
[0017] FIG. 3A illustrates a top view of proximate sensing
substrate positions and available sensing areas according to one
implementation of this disclosure.
[0018] FIG. 3B illustrates the top view of FIG. 3A with sensing
substrate positions and additional proximate sensing areas
available according to one implementation of this disclosure.
[0019] FIG. 4 illustrates a schematic diagram of the proximate
sensing system of this disclosure utilizing overlapping sensors on
a single substrate according to one implementation of this
disclosure.
[0020] FIG. 5 illustrates a schematic diagram of the proximate
sensing system of this disclosure utilizing side-by-side sensors on
respective separate substrates according to one implementation of
this disclosure.
[0021] FIG. 6A illustrates a top view of a sensor system according
to one embodiment of this disclosure in which sensors are spaced
apart alongside each other on the same side of the same
substrate.
[0022] FIG. 6B illustrates a cross section view of the sensor
system of FIG. 6A according to one embodiment of this disclosure in
which sensors are spaced apart alongside each other on the same
side of the same substrate.
[0023] FIG. 7 illustrates a side view of a sensor system according
to one embodiment of this disclosure in which sensors are
positioned on opposite sides of a single substrate according to one
embodiment of this disclosure.
[0024] FIG. 8 illustrates a side view of a sensor system according
to one embodiment of this disclosure in which a shield layer is
positioned between a source of signal interference and a substrate
incorporating the proximate sensing structures of this
disclosure.
DETAILED DESCRIPTION
[0025] Terms used in this disclosure are given their broadest plain
meanings. For example, this disclosure describes apparatuses and
systems for sensor installations described as "proximate sensors."
Without limiting the disclosure in any way, one way to visualize a
"proximate sensor" is by considering the proximate sensor relative
to a primary hand sensor or primary occupant sensor, including, but
not limited to, capacitive sensors of the prior art. Accordingly, a
proximate sensor may be described as an additional sensing zone
that operates in conjunction with, but separate from, a primary
sensor that has a direct electrical link, typically by a physical
connection, to another computer and voltage source, such as the
above described ECU. This disclosure does not limit the kinds of
sensors that may be considered a primary sensor, but a primary
sensor often utilizes a wired connection to initiate and monitor
changes in capacitance due to the presence of an occupant or other
conductive object near the primary sensor. A wired connection
between a primary sensor and an electronic control unit should not
be considered the only kind of primary sensor that can be
supplemented with other embodiments of this disclosure because hand
sensing and occupant sensing could include wireless transmission of
sensor data as well in other configurations.
[0026] The proximate sensor described herein is an electrically
floating sensing surface that is not physically connected or in
direct electrical communication with an electrical control unit or
other computer. Instead, the proximate sensor is positioned very
near the primary sensor that typically does have a physical
electrical connection, whether wired or wireless, to a controller
or other voltage source. The proximate sensor establishes an
additional sensing zone through its position relative to the
primary sensor. For example, when a primary sensor and a proximate
sensor are in a consistent or fixed relative position, the electric
fields established on the primary sensor (for capacitive sensing or
for tracking other physical and electrical phenomena) may also
trigger similar field, current or voltage modulation in a nearby
proximate sensor. In some embodiments, the primary sensory and the
proximate sensor are positioned in a preset dimensional offset
configuration, such as layering on a complex shapes such as a
steering wheel rim. Due to the very near (0 to 3 mm) positioning,
when the primary circuit is energized by a sensing controller it
charges the proximate sensor circuit. E-fields are setup from a
primary surface of the primary sensor and align to a nearby
secondary surface(s) of a proximate sensor. Due to the free
electrons in the secondary, or proximate, sensor it also acts as a
capacitive proximate sensing surface. As the capacitive signal and
therefore e-field, in the primary surface changes, the field
profile of the proximate sensor also changes. If a capacitive load
is applied to the proximate sensor, such as a hand, an occupant's
body, or another conductive object, the e-field interaction between
the secondary, proximate sensor to the primary sensor will be
detectable by the controller.
[0027] The proximate sensing configurations of this disclosure may
provide extended sensing zones to areas in a vehicle that were
previously unavailable for field effect sensing because direct
connections to a controller or other voltage source were too bulky
or cumbersome. This disclosure illustrates that by using a
proximate sensor embodiment, extended sensing zones are established
in very useful vehicle applications.
[0028] For example, and without limiting this disclosure, primary
sensors of the prior art have been used for applications involving
hands-on-heat technology in which the ECU is programmed to provide
certain output electrical signals to sensor circuits or shield
circuits having appropriate resistance to heat a steering wheel or
other vehicle component. In this embodiment, the proximate sensor
may be a metallic material, whether wire or knitted mesh,
conductive inks applied to a flexible substrate, conductive
fabrics, stitched wire, or other metal layer/surface, that is
positioned in an area where capacitive hand sensing is desired.
Even though hands-on-heat can utilize the heating element wire as
the capacitive sensor, it does not provide a sufficient surface
density for sensing as compared to a traditional electrode, such as
a larger 2 mm stitched wire sensor. This is to say that the spacing
between the heating wires for hands-on-heat steering wheel
applications is about 6-8 millimeters. This can result in low
sensitivity or low Q-count charge values and result in poor sensing
margin. Unfortunately, the heating elements used in hands-on-heat
steering assemblies cannot increase in stitching density to less
than 6-8 mm spacing because the heating element wire must be within
a specific heating element resistance of about 1.5 to 2.5 ohms.
Increasing the spacing density of the wire would increase the
heating element resistance from the desired 1.5 to 2.5 ohms, up to
an undesirably large 30-40 ohms. This would result in a heating
function for hands-on-heat steering applications that would not
meet customer heat-up requirements. A solution is needed to allow
both features, hands-on-heat and capacitive sensing, to function
together.
[0029] One kind of problem solved by a proximate sensor described
herein is that additional wire could be stitched next to the
heating element wire, possibly on the same heating layer substrate,
to increase the effective sensing surface, without making an
electrical connection to the heating surface wire. Another solution
would be to place a knitted wire mesh, carbon coated fibers, or
printed conductive ink, on a substrate surface directly below the
heating element substrate material. It could also be positioned
co-planar to the heating wire on the same heating wire substrate.
This would provide a higher density sensing surface without the
complexity of making an additional electrical connection for
sensing.
[0030] The proximate sensor of this disclosure is also available
for use in applications involving rigid or tight fitting materials
for coverings on a steering wheel rim or other vehicle component,
such as wood trim, carbon fiber layers, or specialized polymers
used in vehicle components. For example, the example steering wheel
assembly of the prior art FIG. 1A includes an outer skin 20, such
as but not limited to a standard hand sensing steering wheel with a
leather wrapping. The malleable, somewhat porous nature of leather
and engineered plastic steering wheel wraps would accommodate the
above-described standard primary sensor for integrating hand
sensing in a steering assembly. For steering wheels that utilize
wood trim accents or carbon fiber coverings on at least part of the
steering wheel, manufacturers typically rely on a formed plastic
carrier or shell which the trim material is attached to, and the
shell also provides a proper interface to the steering wheel. It is
possible to metal coat these plastic shells, or load the plastic
with metal particles. It is also possible to use injection molding,
or IML, to attach a metallic surface onto the shell. The problem
with these procedures is that if a surface to be metallized has a
complex shape, it may not be simple to make an electrical
connection to the metallized plastic.
[0031] The solution for sensing in these complex shapes is to
metalize the shell, made of plastic or other polymeric materials,
and position a primary sensor there under, which has an electrical
connection to a voltage source (e.g. an ECU), in close proximity to
the metalized shell. The metallized shell then provides a proximate
sensor relative to the primary sensor because the metallized shell
has a conductive surface on an opposite side relative to the
primary sensor. This addition of a proximate sensor surface can
help provide a level of hand sensing to wood or carbon fiber
covered steering wheels which is not obtainable with the standard
hand sensor under a plastic shell. Furthermore, this kind of
additional proximate sensor can be accommodated without the
difficulties of working with the shell layer at all. For instance,
conductive particles or layers can be added to the material of a
steering wheel outer skin (made of leather or synthetic materials),
making the outer skin a proximate sensor as well.
[0032] This disclosure accounts for engineering developments that
take advantage of steering wheel structures providing excellent
locations for certain accessories. For example, and without
limiting this disclosure, sensors described herein may have to
account for other components, such as the light bar technology
placed on some steering wheels. Light bar installations are
discussed in detail in U.S. Pat. No. 10,036,843, entitled Steering
Wheel Light Bar, which issued from U.S. application Ser. No.
15/137,646 and is incorporated by reference herein. In these kinds
of applications, the light bar presents an engineering problem
because lightbars do not have the ability to provide hand sensing
over the lightbar lens. Proximate sensing could be used to provide
a level of hand sensing directly over the lightbar lens if the lens
has a metallic surface either on top or just under the plastic
housing. Different methods exist to add this kind of conductivity
to a plastic lens. A conductive lens could be used as the primary
e-field source, and a proximate sensor could be positioned nearby
that would establish non-physical electrical communication with the
fields generated by the conductive lens and provide a sensor
circuit positioned near the outside area of the lens.
[0033] The figures of this disclosure illustrate numerous
embodiments that can be used to establish a proximate sensor
relative to a primary sensor having a direct electrical connection
to a voltage source and computer. These embodiments provide
efficient methods to transmit capacitive signals to a secondary or
proximate sensing surface without that proximate sensing surface
requiring a direct physical connection to a controller. The
embodiments provide several benefits including (i) increased
sensing area and charge density while continuing to use a
traditional current producing method of electrical connection to an
ECU, (ii) increased sensing area and density without changing the
existing sensor layout or connection circuits to the ECU, and (iii)
the above described sensing installations in difficult to reach
areas of a vehicle component.
[0034] FIGS. 2A and 2B show a sensor system that accomplishes these
benefits with a first electrode 216 serving as a primary electrode
with a controller 200 electrically and physically coupled to the
first electrode 216. The controller has computerized hardware such
as a processor and a memory, the memory storing computer executable
instructions for execution by the processor. The computer
executable instructions execute software commands that apply a
voltage to the first electrode 216 to generate an electric field
around the first electrode, which in turn causes the processor to
receive an electrical signal back from the first electrode via a
connected circuit 236. Continuing with FIG. 2A, the system further
includes a second electrode 266, at least a portion of the second
electrode being disposed within the electrical field generated by
the first electrode, and the second electrode 266 operates while
being physically decoupled from the controller 200. The electrical
field generated by the first electrode 216 induces a corresponding
charge on the second electrode 266, and proximity of a conductive
material on or near the first or second electrode alters the
electrical signal received back by the controller 200 from the
first electrode 216. The conductive material may be a vehicle
occupant's hand, another body part, or any object that adjusts the
electric field exhibited by the first electrode 216. The sensor
system of FIG. 2A illustrates that a controller output transmitted
to the first electrode via circuit loop 236 induces the electric
field and sets a baseline signal for comparing to the electrical
signal received back from the first electrode 216 by the controller
processor.
[0035] The first electrodes 216, 316, 416, 515, 616, 716, 816 and
second electrodes 266, 366, 466, 566, 666, 766, and 866 of the
systems shown in the figures represent the primary electrode and
the proximate electrode, respectively, as discussed in the above
description. At least a portion of each second electrode, operating
as a proximate sensor, is in a position that is spaced apart from
and extends alongside at least a corresponding portion of the first
electrode. The term "spaced apart" is given its broadest meaning
and includes all embodiments by which the first and second
electrodes are distinguished by separation that defines a void
between the electrodes. In other embodiments, the void between the
electrodes may include a filler within the void, such as an
adhesive or any other structure that is necessary for the
application at hand. FIG. 2B illustrates that for embodiments in
which the first electrode 216 and the second electrode 266 overlap
but still have a spaced apart relationship, an adhesive or other
filler 256 separates the electrodes. In some embodiments, such as
that of FIG. 5 discussed below, entireties of both the second
electrode and the first electrode are spaced apart from each other
without overlap and the adhesive or other filler 256 is therefore
not necessary in every embodiment. Depending on the installation at
hand, each first electrode 216, 316, 416, 516, 616, 716, 816 and
each second electrode 266, 366, 466, 566, 666, 766, 866 may be
positioned on a single, common substrate or respective substrates,
as discussed herein. In embodiments with separate substrates, the
goals and operation parameters of the system may be met when the
first and second substrates allow for the above described electrode
overlap or in other embodiments, the first substrate is spaced
apart from the second substrate, at least in part.
[0036] Each of the figures of this disclosure illustrate how a
conductive material (e.g., a hand to be sensed, an occupant to be
sensed, or a conductive object to be sensed) will provide a
distinct and measurable change in the electrical signal transmitted
back to an ECU if the sensed conductive material is proximate the
first, or primary, electrode as shown at reference 375 in FIG. 3A
or if the sensed conductive material is proximate the second, or
proximate sensor, electrode as shown at reference 375 in FIG. 3B.
The proximate sensor portion of the system, illustrated in the
figures as the second electrode 266, 366, 466, 566, 666, 766, 866
extends the active surface area that a conductive material can
interact with and modulate the tracked electric fields of a given
installation.
[0037] FIGS. 2A, 2B, 3A, 3B, and 4 illustrate embodiments of this
disclosure in which the respective first electrode (the primary
sensor) and second electrode (the proximate sensor) overlap when
viewed from above but are separated by space or a filler, such as
an adhesive when viewed in cross section (i.e., the electrodes are
not allowed to short circuit by direct touch). Described another
way, in an x-y-z coordinate system, the first substrate and the
second substrate overlap at a plurality of x-axis and y-axis
coordinates and are spaced apart along a z-axis, the system further
including an adhesive extending between overlapping regions of the
first substrate and the second substrate.
[0038] Numerous options are available for the relative positions of
the first electrodes serving as primary electrodes or primary
sensors, the second electrodes serving as proximate sensors, and
the substrates used to support each. FIG. 4 illustrates how the
primary sensor 416 and the proximate sensor 466 are allowed to
overlap, separated by a filler or adhesive, on the same side of a
substrate 450. FIGS. 5, 6A and 6B show the sensors spaced apart
(with or without other material therebetween), and the substrates
are still operated within common electric fields, monitored by an
ECU 200, when the electrodes and even respective substrates are
spaced apart in a generally aligned position on either the same or
separate substrates. FIG. 7 illustrates that the sensors 716, 766
may be positioned on opposite sides of a single substrate 750, and
the operational principles still apply when a perimeter of the
second electrode is within and spaced apart from a respective
perimeter of the first electrode.
[0039] The ECU 200 of each embodiment disclosed herein may have
respective computerized controls to initiate the output signals
that prompt electric fields around the primary electrode and the
proximate sensing electrode. As noted above, the ECU transmits an
output electrical signal onto the first, primary electrode, which
initiates an electric field around at least the first electrode.
The circuits connecting the first electrode and the ECU sense the
electric fields about the first electrode by a return signal from
the first electrode back to the ECU. The return signal can be
tracked by capacitive sensing, current sensing, or changes in
voltage picked up by the ECU that is typically in a physical
connection with the first, or primary sensor, electrode.
[0040] The arrangement of mutual field sensing at a first electrode
serving as a primary sensor and at a second electrode serving as a
proximate sensor has numerous applications in vehicle operation. In
one embodiment, the controller transmits a first electrical input
to the first electrode that generates heat directed to a steering
wheel of a vehicle and the controller transmits a second electrical
input to the first electrode that induces the corresponding sensing
charge on the second electrode, wherein the first and second
electrical inputs are time multiplexed. As shown in FIG. 8, the
sensor system may include a third electrode disposed between a
steering wheel frame and the first and second electrodes as a pair,
the third electrode 870 being physically and electrically coupled
to the controller, and the computer executable instructions further
cause the processor to transmit on another circuit 836B a third
electrical output to the third electrode that shields the first
electrical input and the second electrical input on the first
electrode from the frame 880 of the steering wheel.
[0041] Details of the electrode structures may be adjusted for the
installation at hand. In one embodiment, the first electrode has a
first end portion and a second end portion, the first end portion
being physically coupled to the controller and the second end
portion being spaced apart from the first end portion. A respective
end portion of the second electrode is disposed adjacent the second
end portion of the first electrode within the electric field of the
second end portion of the first electrode. This embodiment would
include, therefore, the overlapping ends of FIGS. 2 and 3 or the
spaced apart ends of FIG. 5. Certain structural details provide
numerous options in forming the sensing system disclosed herein. In
different embodiments, that may be combined in numerous
combinations, overlapping electrodes may be spaced apart by a
non-conductive adhesive or other filler filling the space between
the electrodes. In other embodiments, the first and second
electrode may include a conductive fabric. The conductive fabric
may include a non-conductive substrate and conductive wires woven
through the non-conductive substrate. The second electrode may
provide a proximate sensing surface in the form of a wire mesh. The
second electrode may further include a coating of a conductive
material on a surface of a vehicle component. All of these
embodiments are configured to be installed for use on various
components of a vehicle, such as a but not limited to installations
in which the first and second electrodes are disposed adjacent a
steering wheel frame of a vehicle. At least a portion of the first
and/or second electrode may be disposed adjacent a rim portion of
the steering wheel frame. In other embodiments, the first and
second electrodes are disposed adjacent a seat frame in a vehicle
or on other components of a vehicle in which field sensing is
useful.
[0042] In other descriptions of the sensors and associated systems,
a primary electrode may be positioned on or within a physically
accessible object, and a controller is connected to the primary
electrode such that a charging source subject to the controller
charges the primary electrode, wherein, upon the charging, the
controller is configured to receive an electrical signal back from
the primary electrode. As noted above, the second electrode,
referred to as a proximate electrode or proximate sensor, functions
as a floating electrode that is mechanically disconnected from
outside charging sources. At least a portion of the floating
electrode is aligned with the primary electrode on or within the
accessible object (e.g., a vehicle component) such that upon the
charging of the first electrode, the second electrode exhibits an
induced current thereon. In operation, wherein, proximity of a
conductive material to either the primary electrode or the floating
electrode induces capacitive coupling between the conductive
material and the respective primary or floating electrode that
alters the electrical signal received by the controller from the
first electrode. The controller is configured to track a response
of the electrical signal to the capacitive coupling. The portion of
the floating electrode aligned with the primary electrode is also
spaced apart from the primary electrode, such that when the
conductive material is proximate the aligned portion of the
floating electrode, the capacitive coupling changes a baseline
capacitance at the aligned portion present upon charging the
primary electrode. The dimensional references of this disclosure
are not limiting but provide examples for perspective. For example,
in some embodiments, the floating and primary electrodes are spaced
apart by a dimension between 0 and 3 millimeters, inclusive of the
endpoints 0 mm and 3 mm. In some embodiments, the floating
electrode and the primary electrode are spaced apart in a common
plane intersecting each electrode. Another way to describe the
electrode positions in these embodiments is that the primary
electrode and the floating electrode are parallel to each other on
a common substrate.
[0043] Without limiting the embodiments to any particular positions
or roles in a system, in some embodiments, the primary electrode is
a heating element and the floating electrode is a capacitive
sensing element. The floating electrode and the primary electrode
may be offset from one another in a constant dimensional amount.
The controller uses the electrical signal to identify changes in an
electrical field strength about the primary electrode due to the
proximity of the conductive material. The controller is configured
to track changes in the electrical field strength (i.e., amplitude
and phase) about the primary electrode, and these changes on the
primary electrode can be analyzed to model interactions present
between the electrical fields on the primary electrode and
corresponding electric fields on the secondary electrode. This
data, therefore, allows for monitoring touch events on both the
primary and secondary electrodes.
[0044] This disclosure is further supported by testing results
utilizing a sensor system as disclosed herein and an ECU that
analyzes the electrical signal received from the primary electrode.
The ECU determined a baseline charge count (Q) for the primary
sensor system, wherein the Q count is a ratio of electromagnetic
energy stored by the primary electrode to the electromagnetic
energy dissipated to the environment per charging cycle. The
controller was further configured to identify changes in the
baseline Q charge count upon the primary sensor exhibiting
capacitive coupling with a conductive material such as an
occupant's hand. The controller was also configured to identify
changes in the baseline Q charge count upon the primary sensor
exhibiting capacitive coupling that has been altered by electric
field effects of a proximate sensor used as disclosed herein.
[0045] Example Test Observation 1
[0046] 1. The test was conducted on a 1-zone hands on wheel sensor
installation using 2 mm spaced sensing wire with no sensing wire on
the steering wheel rim at the 5-7 o'clock area.
[0047] 2. The sensing wire was formed as a 5 mm wide by 150 mm long
sensing electrode having an extension of 170 mm making the total
length of the overall sensor 320 mm. The sensing electrode that was
originally 5 mm wide and 150 mm long includes the extension that is
about 30 mm wide along the extension's 170 mm length.
[0048] 3. The sensing electrode was made of 0.0035 inch monel wire
with a 270 density figure.
[0049] 4. The 5 mm section was wrapped around the steering wheel
rim with the width overlapping a few millimeters to form a "normal
sensing area" with a primary electrode. The extension (e.g., about
170 mm long and 30 mm wide) was positioned over the 5-7 o'clock
steering wheel section and over the trim material attached over the
rim of the steering wheel to form secondary sensor, also referred
to herein as a "proximate sensing area" such that at the 5-7
o'clock steering wheel position the proximate sensing area operates
without overlapping the primary sensing area, and then overlaps the
primary sensing area for the remainder of the extension length.
[0050] 5. The controller software determining the charge count (Q)
was calibrated to zero in the absence of a conductive material
(i.e., a hand) on the primary sensor.
[0051] 6. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 53 Q.
[0052] 7. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 85 Q.
[0053] 8. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 45 Q.
[0054] 9. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 45 Q.
[0055] Example Test Observation 2
[0056] 1. The test was conducted on a 1-zone hands on wheel sensor
installation using 2 mm spaced sensing wire with no sensing wire on
the steering wheel rim at the 5-7 o'clock area.
[0057] 2. The sensing wire was formed as a 30 mm wide by 320 mm
long sensing electrode.
[0058] 3. The sensing electrode was made of 0.0035 inch monel wire
with a 270 density figure.
[0059] 4. The sensing electrode was wrapped around the steering
wheel rim with the width overlapping a few millimeters to form a
"normal sensing area" with a primary electrode around the rim other
than the portions located at the 5-7 o'clock positions. The
remainder of the sensing electrode was positioned over the 5-7
o'clock steering wheel section and over the trim material attached
over the rim of the steering wheel to form secondary sensor, also
referred to herein as a "proximate sensing area" such that at the
5-7 o'clock steering wheel position the proximate sensing area
operates without overlapping the primary sensing area, and then
overlaps the primary sensing area for the remainder of the
extension length.
[0060] 5. The controller software determining the charge count (Q)
was calibrated to zero in the absence of a conductive material
(i.e., a hand) on the primary sensor.
[0061] 6. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 52 Q.
[0062] 7. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 80 Q.
[0063] 8. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 115 Q.
[0064] 9. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 115 Q.
[0065] Example Test Observation 3
[0066] 1. The test was conducted on a 1-zone hands on wheel sensor
installation using 2 mm spaced sensing wire with no sensing wire on
the steering wheel rim at the 5-7 o'clock area.
[0067] 2. The sensing wire was formed as a 30 mm wide by 320 mm
long sensing electrode.
[0068] 3. The sensing electrode was made of 0.0035 inch monel wire
with a 270 density figure.
[0069] 4. The sensing electrode length of 170 mm was wrapped around
the steering wheel rim with the width overlapping a few millimeters
to form a "normal sensing area" with a primary electrode around the
rim other than the portions located at the 5-7 o'clock positions.
The remainder of the sensing electrode was positioned over the 5-7
o'clock steering wheel section and over the trim material attached
over the rim of the steering wheel to form a secondary sensor, also
referred to herein as a "proximate sensing area" such that at the
5-7 o'clock steering wheel position the proximate sensing area
operates without overlapping the primary sensing area, and then
overlaps the primary sensing area for the remainder of the
extension length.
[0070] 5. The controller software determining the charge count (Q)
was calibrated to zero in the absence of a conductive material
(i.e., a hand) on the primary sensor.
[0071] 6. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 55 Q.
[0072] 7. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the normal sensing area induced a
charge count of 75 Q.
[0073] 8. A two finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 166 Q.
[0074] 9. A four finger touch by an occupant (>95.sup.th
percentile occupant class) on the secondary, proximate sensing area
induced a charge count of 166 Q.
[0075] Disclosed are components that can be used to perform the
methods and systems of this disclosure. These and other components
are disclosed herein, and it is understood that when combinations,
subsets, interactions, groups, etc. of these components are
disclosed that while specific reference of each various individual
and collective combinations and permutation of these may not be
explicitly disclosed, each is specifically contemplated and
described herein, for all methods and systems. This applies to all
aspects of this application including, but not limited to, steps in
disclosed methods. Thus, if there are a variety of additional steps
that can be performed it is understood that each of these
additional steps can be performed with any specific embodiment or
combination of embodiments of the disclosed methods.
[0076] As will be appreciated by one skilled in the art, the
methods and systems may take the form of an entirely hardware
embodiment, an entirely software embodiment, or an embodiment
combining software and hardware aspects. Furthermore, the
apparatuses, methods and systems may take the form of a computer
program product on a computer-readable storage medium having
computer-readable program instructions (e.g., computer software)
embodied in the storage medium. More particularly, the present
methods and systems may take the form of web-implemented computer
software. Any suitable computer-readable storage medium may be
utilized including hard disks, CD-ROMs, optical storage devices, or
magnetic storage devices.
[0077] Computer program instructions making up the computer
software may also be stored in a computer-readable memory that can
direct a computer or other programmable data processing apparatus
to function in a particular manner, such that the instructions
stored in the computer-readable memory produce an article of
manufacture including computer-readable instructions for
implementing the function specified in the flowchart block or
blocks. The computer program instructions may also be loaded onto a
computer or other programmable data processing apparatus to cause a
series of operational steps to be performed on the computer or
other programmable apparatus to produce a computer-implemented
process such that the instructions that execute on the computer or
other programmable apparatus provide steps for implementing the
functions specified in the flowchart block or blocks.
[0078] Described herein are embodiments of a computer readable
medium used to support the sensor systems of this disclosure. The
figures present an overview of an embodiment of a computer readable
medium for use with the methods disclosed herein. Results can be
delivered to a gateway (remote computer via the Internet or
satellite) for in graphical user interface format. The described
system can be used with an algorithm, such as those disclosed
herein.
[0079] As may be understood from the figures, in this
implementation, the computer may be in the form of the above
described electronic control unit (ECU) 200 and include a computer
processing unit 206 that communicates with other elements. Also
included in the computer readable medium may be any number of
output devices 212 and input devices 214 for receiving and
displaying data. This display device/input device may be, for
example, a keyboard or pointing device that is used in combination
with a monitor. The computer system may further include at least
one storage device 210, such as a hard disk drive, a CD Rom drive,
SD disk, optical disk drive, or the like for storing information on
various computer-readable media, such as a hard disk, a removable
magnetic disk, or a CD-ROM disk. As will be appreciated by one of
ordinary skill in the art, each of these storage devices may be
connected to the system bus by an appropriate interface. The
storage devices and their associated computer-readable media may
provide nonvolatile storage. It is important to note that the
computer described above could be replaced by any other type of
computer in the art. Such media include, for example, magnetic
cassettes, flash memory cards and digital video disks.
[0080] Further comprising an embodiment of the system can be a
network interface controller 215. One skilled in the art will
appreciate that the systems and methods disclosed herein can be
implemented via a gateway that comprises a general-purpose
computing device in the form of a computing device or computer.
[0081] One or more of several possible types of bus structures can
be used as well, including a memory bus or memory controller, a
peripheral bus, an accelerated graphics port, and a processor or
local bus using any of a variety of bus architectures. By way of
example, such architectures can comprise an Industry Standard
Architecture (ISA) bus, a Micro Channel Architecture (MCA) bus, an
Enhanced ISA (EISA) bus, a Video Electronics Standards Association
(VESA) local bus, an Accelerated Graphics Port (AGP) bus, and a
Peripheral Component Interconnects (PCI), a PCI-Express bus, a
Personal Computer Memory Card Industry Association (PCMCIA),
Universal Serial Bus (USB) and the like. The bus, and all buses
specified in this description can also be implemented over a wired
or wireless network connection and each of the subsystems,
including the processor, a mass storage device, an operating
system, network interface controller, Input/Output Interface, and a
display device, can be contained within one or more remote
computing devices at physically separate locations, connected
through buses of this form, in effect implementing a fully
distributed system.
[0082] The computer typically comprises a variety of computer
readable media. Exemplary readable media can be any available media
that is accessible by the computer and comprises, for example and
not meant to be limiting, both volatile and non-volatile media,
removable and non-removable media. The system memory comprises
computer readable media in the form of volatile memory, such as
random access memory (RAM), and/or non-volatile memory, such as
read only memory (ROM).
[0083] In another aspect, the ECU 200 can also comprise other
removable/non-removable, volatile/non-volatile computer storage
media. For example and not meant to be limiting, a mass storage
device can be a hard disk, a removable magnetic disk, a removable
optical disk, magnetic cassettes or other magnetic storage devices,
flash memory cards, CD-ROM, digital versatile disks (DVD) or other
optical storage, random access memories (RAM), read only memories
(ROM), electrically erasable programmable read-only memory
(EEPROM), and the like.
[0084] Optionally, any number of program modules can be stored on
the mass storage device, including by way of example, an operating
system and computational software. Each of the operating system and
computational software (or some combination thereof) can comprise
elements of the programming and the computational software. Data
can also be stored on the mass storage device. Data can also be
stored in any of one or more databases known in the art. Examples
of such databases comprise, DB2.TM., MICROSOFT.TM. ACCESS,
MICROSOFT.TM. SQL Server, ORACLE.TM., mySQL, PostgreSQL, and the
like. The databases can be centralized or distributed across
multiple systems.
[0085] The ECU 200 can operate in a networked environment. By way
of example, a remote computing device can be a personal computer,
portable computer, a server, a router, a network computer, a peer
device, sensor node, or other common network node, and so on.
Logical connections between the computer and a remote computing
device can be made via a local area network (LAN), a general wide
area network (WAN), or any other form of a network. Such network
connections can be through a network adapter. A network adapter can
be implemented in both wired and wireless environments. Such
networking environments are conventional and commonplace in
offices, enterprise-wide computer networks, intranets, and other
networks such as the Internet.
[0086] Any of the disclosed methods can be performed by computer
readable instructions embodied on computer readable media. Computer
readable media can be any available media that can be accessed by a
computer. By way of example and not meant to be limiting, computer
readable media can comprise "computer storage media" and
"communications media." "Computer storage media" comprise volatile
and non-volatile, removable and non-removable media implemented in
any methods or technology for storage of information such as
computer readable instructions, data structures, program modules,
or other data. Exemplary computer storage media comprises, but is
not limited to, RAM, ROM, EEPROM, flash memory or other memory
technology, CD-ROM, digital versatile disks (DVD) or other optical
storage, magnetic cassettes, magnetic tape, magnetic disk storage
or other magnetic storage devices, or any other medium which can be
used to store the desired information and which can be accessed by
a computer.
[0087] The methods and systems described herein can employ
Artificial Intelligence techniques such as machine learning and
iterative learning. Examples of such techniques include, but are
not limited to, expert systems, case based reasoning, Bayesian
networks, behavior based AI, neural networks, fuzzy systems,
evolutionary computation (e.g. genetic algorithms), swarm
intelligence (e.g. ant algorithms), and hybrid intelligent systems
(e.g. Expert inference rules generated through a neural network or
production rules from statistical learning).
[0088] The embodiments of the method, system and computer program
product described herein are further set forth in the claims
below.
[0089] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art. Methods and materials similar or
equivalent to those described herein can be used in the practice or
testing of the present disclosure. As used in the specification,
and in the appended claims, the singular forms "a," "an," "the"
include plural referents unless the context clearly dictates
otherwise. The term "comprising" and variations thereof as used
herein is used synonymously with the term "including" and
variations thereof and are open, non-limiting terms. While
implementations will be described for steering wheel hand detection
systems, it will become evident to those skilled in the art that
the implementations are not limited thereto.
[0090] As utilized herein, the terms "approximately," "about,"
"substantially", and similar terms are intended to have a broad
meaning in harmony with the common and accepted usage by those of
ordinary skill in the art to which the subject matter of this
disclosure pertains. It should be understood by those of skill in
the art who review this disclosure that these terms are intended to
allow a description of certain features described and claimed
without restricting the scope of these features to the precise
numerical ranges provided. Accordingly, these terms should be
interpreted as indicating that insubstantial or inconsequential
modifications or alterations of the subject matter described and
claimed are considered to be within the scope of the invention as
recited in the appended claims.
[0091] It should be noted that the term "exemplary" as used herein
to describe various embodiments is intended to indicate that such
embodiments are possible examples, representations, and/or
illustrations of possible embodiments (and such term is not
intended to connote that such embodiments are necessarily
extraordinary or superlative examples).
[0092] The terms "coupled," "connected," and the like as used
herein mean the joining of two members directly or indirectly to
one another. Such joining may be stationary (e.g., permanent) or
moveable (e.g., removable or releasable). Such joining may be
achieved with the two members or the two members and any additional
intermediate members being integrally formed as a single unitary
body with one another or with the two members or the two members
and any additional intermediate members being attached to one
another.
[0093] References herein to the positions of elements (e.g., "top,"
"bottom," "above," "below," etc.) are merely used to describe the
orientation of various elements in the FIGURES. It should be noted
that the orientation of various elements may differ according to
other exemplary embodiments, and that such variations are intended
to be encompassed by the present disclosure.
[0094] It is important to note that the construction and
arrangement of the sensing system for a steering wheel as shown in
the various exemplary embodiments is illustrative only. Although
only a few embodiments have been described in detail in this
disclosure, those skilled in the art who review this disclosure
will readily appreciate that many modifications are possible (e.g.,
variations in sizes, dimensions, structures, shapes and proportions
of the various elements, values of parameters, mounting or layering
arrangements, use of materials, colors, orientations, etc.) without
materially departing from the novel teachings and advantages of the
subject matter described herein. For example, elements shown as
integrally formed may be constructed of multiple parts or elements,
the position of elements may be reversed or otherwise varied, and
the nature or number of discrete elements or positions may be
altered or varied. The order or sequence of any process or method
steps may be varied or re-sequenced according to alternative
embodiments. Other substitutions, modifications, changes and
omissions may also be made in the design, operating conditions and
arrangement of the various exemplary embodiments without departing
from the scope of the present embodiments.
[0095] Although the subject matter has been described in language
specific to structural features and/or methodological acts, it is
to be understood that the subject matter defined in the appended
claims is not necessarily limited to the specific features or acts
described above. Rather, the specific features and acts described
above are disclosed as example forms of implementing the
claims.
* * * * *